<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>后盾人</title>
    <style>
        * {
            padding: 0;
            margin: 0;
        }

        body {
            width: 100vw;
            height: 100vh;
            background: #34495e;
            display: grid;
            grid-template: 1fr/repeat(5, 1fr);
        }

        div {
            grid-column: 3/4;
            height: 50px;
            width: 50px;
            border-radius: 50%;
            background: #e67e22;
            justify-self: center;
            animation-name: move;
            animation-duration: 4s;
            animation-iteration-count: infinite;
        }

        @keyframes move {
            0% {
                transform: translateY(0vh);
                transition-timing-function: ease-in;
            }

            30% {
                transform: translateY(10vh);
                transition-timing-function: ease-in;
            }

            60% {
                transform: translateY(40vh);
                transition-timing-function: ease-in;
            }

            80% {
                transform: translateY(60vh);
                transition-timing-function: ease-in;
            }

            95% {
                transform: translateY(75vh);
                transition-timing-function: ease-in;
            }

            15%,
            45%,
            75%,
            85%,
            100% {
                transform: translateY(90vh);
                transition-timing-function: ease-out;
            }
        }
    </style>
</head>

<body>
    <div></div>
</body>

</html>